So you want to get into Y Combinator? Here’s how

Y Combinator, the popular startup incubator, unleashed its newest batch of fledgling technology companies into the world at its Summer 2011 Demo Day event last month. At six years old, Y Combinator is a veteran of sorts in the fast-paced world of Silicon Valley innovation. But the quality of its latest startup class — and the interest it’s received from the tech industry’s most powerful investors — showed that YC is sharper than ever at choosing top-notch entrepreneurs and helping them shape solid startups.

And the search is already on for the next class of potential startup superstars. Y Combinator is currently accepting applications for the winter 2012 funding cycle, and the competition is stiff: Y Combinator generally accepts only three percent of the applications it receives, an acceptance rate lower than MIT or Harvard.

I recently sat down with Y Combinator co-founder Jessica Livingston to find out what YC’s partners look for in entrepreneurs — you can watch our video below. Here are a few of her main points:

Co-founders should be buddies. Y Combinator prefers founding teams that consist of two or three people — and the friendlier they are with each other, the better. People who just met each other a month ago and decided to start a company usually raise YC’s red flags.

Hackers necessary. Being technical is important for the YC folks; Livingston is the only member of YC’s three-person founding team who does not know how to code. While they’ve loosened up their standards a bit by allowing in non-technical co-founders, YC insists that at least one member of a founding team have serious technical chops.

Flexibility is everything. If you’re a control freak, you probably won’t fit in at Y Combinator. YC looks for founders who are willing to take advice — and change everything about their startup if it’s not working out. Determination is important, but folks who seem stubborn during their YC interviews won’t make the cut.